1. Field of the Invention
The invention relates to the field of micro-electro-mechanical systems (MEMS) and in particular to the use of micro and nanobeads in MEMS.
2. Description of the Prior Art
There has been a great deal of interest in integrating special micro-scale particles on a chip, especially in micro-electro-mechanical systems (MEMS). There are already many applications of microparticles in MEMS and even more are expected once particles can be easily integrated and localized. Fluorescent and dyed particles are frequently used in microfluidic devices for flow visualization. Magnetic microbeads can be manipulated in micro devices for future transportation of chemical reagents and cells. One-time microvalves and micropumps have been demonstrated using expandable microspheres. Pressures in excess of 8000 psi have been achieved using silica beads packed capillaries. Special microspheres have been demonstrated for multianalyte sensor arrays for the analysis of complex fluids containing a variety of important classes of analytes.
However, none of these applications directly integrates particles into the subject system. Instead, the particles are usually injected through access holes or placed by micromanipulators after device fabrication. Since these are not batch processes and have to be done die by die, it is impractical and cost-ineffective to make integrated miniaturized systems. Hence, an easy, inexpensive, batch process is needed. The invention satisfies these requirements.